Hi, I did have the same problem as you have right now. NME support for softkeyboard is rather lacking right now, it still missing API implementation from AIR for Mobile.
Somethings that might help:
- To track whether softkeyboard is visible or not, you can watch the textfield focus (on focus/lost focus) and assume when the textfield is focused, the softkeyboard is visible. Then from there you can calculate your textfield Y position is it below the keyboard treshold (I use half the screen height), if it is, push the whole stage/scene up, so the textfield is visible. When the softkeyboard is invisible again (textfield lost focus) you can return its position to its original position.
- About the return key, the softkeyboard will be hidden itu the user touches area outside the keyboard OR the back button. My problem was detecting the back button when the softkeyboard is visible, because it throw out a slightly different keyboard event/code. You can edit/modify the GameActivity.java and use the template tag in the NMML to add the functionality (return key hide the keyboard).